#include<iostream>

using namespace std;

void beforebefore() {
    cout<<"hello !!";
}

void before() {
    cout<<"hello !!";
}

void a() {
    cout<<"hello world!!!!!";
    cout<<"by b";
    cout<<"by a2";
    cout<<"by b2";
}

void after() {
    cout<<"hello !!";
}

int main() {
    after();
    a();
    before();
    beforebefore();
    return 0;
}